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Crofty
10-12-2005, 07:30 PM
Hi was out on the CX today, then the rear brake decided to bind, disk was bright red (stopped in the middle of a blind S-bend!) had to stop, let it cool and worked the brake pedal, I got home. But why did it do it and what will prevent it?
Freak
10-12-2005, 07:31 PM
Hi was out on the CX today, then the rear brake decided to bind, disk was bright red (stopped in the middle of a blind S-bend!) had to stop, let it cool and worked the brake pedal, I got home. But why did it do it and what will prevent it?

Sounds like it needs a good cleanout and some fresh fluid
Grav
10-12-2005, 07:31 PM
Your rear calliper is probably full of crud and is sticking. Remove and clean it and that should sort it.
Dougie
10-12-2005, 07:38 PM
Check the disc,heating it up to red hot can do funny things to the metallurgy.
Grav
10-12-2005, 07:39 PM
Yep, it can anneal it and make it warp.
Dougie
10-12-2005, 07:41 PM
Not to mention crack and break up (in extreme cases). :eek:
Grav
10-12-2005, 07:47 PM
Has to get really really really hot to do that Dougie. Happens a lot in NASCAR racing.
Dougie
10-12-2005, 07:49 PM
True,but we don't know the history of the bike.It may have done it many times before,we just don't know. :D Or it may be a crap disc.
Grav
10-12-2005, 07:54 PM
Only one way to find out and thats ask. :D
bad toad
10-12-2005, 07:54 PM
i,ll try to put it east to understand the main reason the caliper siezes is due to corrosion behind the seals some times you can get away with stripping the caliper down and cleaning out the grooves the seals sit in and giving the piston a good polish (though not really recommended) and rebuilding using clean fluid on reassembly!!! caliper kits are not dear! as for the disc if its scored or discoloured replace it!!! err on the safe side if in doubt replace it!!
Crofty
10-12-2005, 08:12 PM
Great. My tools are in retto. I'll have to get her there soon.
Bless 'im, my bro lifted the bike up a kerb to get it off the road.
Dougie
10-12-2005, 08:14 PM
Get it sorted soon as m8,rear wheel lock up ain't funny.
Hairy Stores
10-12-2005, 08:48 PM
It don't take much to warp a disc, I rode to Gt. Yarmouth and back once with a slightly sticky caliper without realising it, :o just the heat generated by that was enough, had to replace the disc :(
Dougie
10-12-2005, 08:50 PM
Older machines like the CX have thicker discs than modern bikes,don't wear out as quick or warp as easy.Mind you,they don't work as well either.......
Hairy Stores
10-12-2005, 08:56 PM
Older machines like the CX have thicker discs than modern bikes,don't wear out as quick or warp as easy.Mind you,they don't work as well either.......

Sad to say this was an older bike, thick discs OK but still warped :(
If the disc's been heated to red it'll be buggrd
Crofty
10-12-2005, 10:33 PM
Balls, well I'll rebuild the caliper, if the disk's not completely fooked, I'tll have to do till the next MOT I ain't got the money.
dracken1
11-12-2005, 12:21 AM
a disc for that bike shouldn't be to expensive, i'll look it up :)
Taff
11-12-2005, 12:31 AM
The tiny fluid return hole in the cylinder is blocked, so every time you work the brake, it pumps fluid in, moves the pistons, but cant let it return when it should.
Clean the master cylinder holes out.
ughesh
11-12-2005, 01:58 AM
Never seen a CX with a rear disc brake :confused:
Crofty
11-12-2005, 03:29 AM
It's the eurosport, one of the later ones.
Thanks for your advice everyone, I'll try and get 'er back to retford next week. on the oil-covered front brake, should be fun! Once she's in Ma and Pa's garage i should be able to get some work done and be all nice and spangly for spring!